1. Technical Field
The present invention relates to a liquid droplet ejection apparatus of an inkjet type for plotting on a workpiece by a plurality of head units each of which has more than one functional liquid droplet ejection heads as a supply unit, with supplying functional liquid to the plurality of head units respectively, a method of manufacturing an electro-optical apparatus, and an electro-optical apparatus.
2. Related Art
A liquid droplet ejection apparatus is known as an inkjet printer corresponding to six colors which plots on a workpiece, except the liquid droplet ejection apparatus of the kind described above. The liquid droplet ejection apparatus has a functional liquid supplying apparatus which includes four inkjet heads per color, two intermediate ink packs per color supplying ink to the four inkjet heads per color, an ink cartridge per color replenishing functional liquid in the two intermediate ink packs per color, and tube units connecting these elements. JP-A-2003-118136 is an example of related art. Note that the ink cartridge is, so called, a main tank, which is replaced when a reduction of a liquid therein is detected.
However, in the inkjet printer described above, when the ink cartridge is replaced, timings at which a new ink arrives to respective inkjet heads are different each other because an ink consumption amount of each of the inkjet head is different according to a plotting pattern (print image). On the other hand, in a liquid droplet ejection apparatus of inkjet type used for manufacturing color filters or organic EL apparatuses, special functional liquid (inks) is used such as a filter material or a luminescent material and so on. When the functional liquid supplying apparatus above is incorporated in the liquid droplet ejection apparatus like this, some functional liquid droplet ejection heads eject old functional liquid whereas other functional liquid droplet ejection heads eject new functional liquid, thereby the plotting is performed on the workpiece with old and new functional liquid. In this case, there is a possibility that the plotting is performed with functional liquid of which production lots are different as the old and new functional liquid, that is, with functional liquid having different properties in viscosity and the like because of a problem regarding manufacturing of precision. In this case, a plotting quality for the workpiece to be plotted is deteriorated because of color heterogeneity or striations on the workpiece.